Control apparatus



June 17 1930. w. H. SMITH 1,764,420

. CONTROL APPARATUS Filed Oct. 9, 1926 3 Sheets-Sheet l WITNESS s;INVENTOR June '17, 1930. w. H. SMITH 4;

CONTROL APPARATUS Filed Oct. 9, 1926 5 sheets sheet 2 TNESS s: v lNVENTOv h a/fierfl 507/772,

June 17, 1930. w. H. SMITH CONTROL APPARATUS Filed Oct. 9, 1926. sSheets-Sheet 5 ATT'ORNEY Patented June 17, 1930 UNITED STATES PATENTOFFICE WALTER H. SMITH, OF WILKINSBURG, PENNSYLVANIA, ASSIGNOR TOWESTINGHOUSE ELECTRIG& MANUFACTURING COMPANY, A CORPORATION OFPENNSYLVANIA CONTROL APPARATUS Application filed October 9, 1926. SerialNo. 140,534.

This invention relates generally to con trol apparatus and moreparticularly to control devices for governing the making and breaking ofa plurality of circuits.

The object of this invention, generally stated, is the provision of acontrol device that shall be simple and 'efiicient in operation, andreadily and] economically manufactured.

A more specific object of the invention is to provide for the operationof a contactor upon the flow of currents of different predeterminedvalues through the contactoractuating coil.

Another object of the invention is to provide for retarding theoperation of an electromagnetioally actuated contactor to give thedesired control of predetermined circuits.

Further objects of the invention will, in part, be obvious and, in part,appear hereinafter.

The invention, accordingly, is disclosed in the embodiment thereof shownin the accompanying drawing, and comprises the features of construction,combination of elements and arrangement of parts which will beexemplified in the construction hereinafter set forth and the scope ofthe application of which will be indicated in the claims.

For a fuller understanding of the nature and objects of the invention,reference should be had to the following detailed description taken inconjunction with the accompanying drawings, in which:

Fig. 1 is a view, partly in side elevation and partly in section, of acontrol device constructed in accordance with this invention;

Fig. 2 is also a View, in side elevation, showing the relation of theoperating members of the control device;

Fig. 3 is a View, in horizontal section, taken along the lines IIIIII ofFig. 1, showing certain features of the construction;

Fig. 4 is a diagrammatic view showing how the control device may beconnected in a circuit; and

Fig. 5 is aview, in side elevation, of a weight provided for retardingthe operation of the control device.

Referring now to the drawing, 10 designates a panel which constitutespart of the frame of the control device. As shown, two frame sections 11and 12, preferably made of some non-magnetizable metal, are mounted onthe panel, one directly above the other.

As illustrated, the upper frame section 11 is provided with threelaterally extending brackets 12 to 14, inclusive, which serve to supporta slidable contact carrier or plunger 15. The upper frame section may bemade from a number of different materials, but it is preferable toconstruct it from a substantially non-magnetizable metal.

As illustrated, a tubular member 16, which is constructed from somenon-magnetic material, such for example, as brass, extends through anopening that is provided in the bracket 12, and is seated on shoulders17 that are formed by a countersunk opening drilled in the bracket 13.In order to retain the tubular member 16 in position, a threaded openingis provided in the bracket 12, and a bolt 18 is mounted therein toengage the upper end of the tubular member.

An actuating coil 19, which is provided for operating the plunger 15, ismounted on the tubular member 16. It will be readily understood that, inassembling the control device, the coil 19 may be set in position on thebracket 13 and the tubular member 16 inserted therethrough to be seatedon the shoulder 17 that is provided in the bracket 13. A spacing member20, preferably of insulating material, is disposed between bracket 12and coil 19. to retain the latter in position.

The plunger or contact carrier 15 comprises a tubular member 21 madefrom some magnetic material, such as iron, and a shank 22 that dependsfrom the lower end of the tubular member. As will be observed, thetubular member 21 is enclosed by a brass tube 2164 which extends abovethe upper end thereof and engages the lower end or head of a guide 23.In this construction, the guide 23 extends into an opening 24 providedin a cap 25. Therefore, the member 23 may be utilized to limit theupward movement of the contact carrier 15.

Both the cap 25 and the guide 23 are made from some non-magnetizablematerial to prevent magnetization and the tendency, which even slightmagnetization would have, to preventthe free operation of the lunger. Inthis particular construction, t e cap 25 is retained in position in theupper end of the tubular member 16 by a clamping bolt18. M

It will be noted that a contact plate 26 is mounted on the shank 22 andis retained in position by means of collars 27 and 28.

In order to prevent the grounding of the contact plate, insulators 29are provided for insulating it from the shank 22 of the plunger.

Two spaced contact members or stationary fingers 30 are mounted on apair of brackets 31 which are carried by the upper frame section 11,being located below the contact plate 26. The contact members 30 may bemade from any suitable material and, in this particular embodiment ofthe invention, are made from resilient leaves or plates of a copperalloy superimposed upon one another.

In mounting the contact members 30, it is necessary to insulate themfrom the remainder of the structure. This result may readilybeaccomplished by making the brackets 31 from some insulating material.As shown, the brackets are attached to the frame 11 by means of studs32, on the outer ends of which a plurality of nuts 33, are mounted to beused as binding posts for conductors adapted to connect the contactmembers 30 in any desired circuit.

As illustrated, the shank 22 of the plunger 15 extends through anopening that is provided in the bracket 14. This shank is utilized forsupporting a weight 34 which is provided torestrict the operation of thecontact plate 26, at predetermined times.

The weight 34 is slidably mounted on the shank 22 and is normallysupported by a nut 35 that is provided on the lower end of the shank-Therefore, by lifting the weight 34, the contact-carrier 15 may bereleased for operation.

In order to lift the weight 34 to permit the plunger 15 to moveindependently thereof, an armature 36 is pivotally mounted at 37 betweenbrackets 38 that are formed integrally with the lower'frame section 12.The upper end of the armature 36 is bifurcated to provide arms 39 and 40which extend on opposite sides of the contact carrier 15 and aredisposed to engage the weight 34.

The armature 36, which simulates a bellcrank, may be actuated by acoil41' that is disposed in alinement with its depending arm 42. The upperarm of the bell-crank, which is slightly curved and bifurcated,

eddy-current action. a

When the coil 41 is deenergized, the armature 36 is retained out ofengagement with the weight 34 bymeans of a spring 45. As shown, thespring 45 is connected between the armature 36 and a lug 46 that isprovided on the lower frame section 12. In connecting the spring 45 tothe armature,

an adjustable set screw 47 is provided in order that the tension ofthespring may be varied at will. As shown in Fig. 2, when the armature issubjected to the action of the spring only, the inner end is seated on ablock 48 that is provided on the frame.

As illustrated in Fig. 5, the weight 34 comprises a hollow annularcasing 34 that is provided with a cap or plug 49. This casing ispartially filled with shot 50 which 7 may be inserted or taken out uponremoval of the cap 49. In this manner, the weight of the member 34 maybe varied at will to meet the operating conditions.

As best shown in Fig. 2, a bent strap contact member 51 is mounted on ascrew bolt 52 and retained in position by means of a spring 53.Thecontact member 51' is loosely mounted on the screw bolt 52 to permitit to move freely. Further, the contact member 51 is disposed inalinement with a contact member 54 that is mounted on the armature 36.In order that the function of the control device hereinbefore describedmaybe clearly understood, its operation, when con-. nected in a simplecircuit, will now be described. p

In the system shown in Fig. 4, my control device is utilized to governthe operation of a sequence drum 55, which is provided to control theconnection of a plurality of single-phase, commutator-type motors 56across the secondary winding 57 of a transformer 58. In thismotor-control system, the motors are started and accelerated byconnecting them across different sections of the secondary windin 57 ofthe transformer 58, in a predetermined sequence, by means of a pluralityof switches 59 to 62, inclusive.

The switches 59 to 62 are of the unitswitch type and are provided withactuating coils, which, for the sake of clearness, will be designated bythe same numeral as the corresponding switch, with the addition of theletter 0. The energization of the switch- I actuating coils may beeffected from any,

suitable source of electric energy, such as a supply circuit 63.

Sequence drum 55 may be actuated in any suitable manner and, in theparticular construction shown, an air-engine 64 of wellknown type may beused. As is common practice, an air-engine, of the type providedforoperating 'a sequence drum and the like, is controlled by twoelectromagnetic valves which are so arranged that the drum moves in onedirection when both of the valves are energized and in the oppositedirection when they are both deenergized and is brought to a stop whenone is energized and the other deenergized. An engine of this type isshown in Patent 1,229,444.

In order to control the operation of the sequence drum, a mastercontroller 65, having a single contact segment 66, is utilized. Asshown, the contact segment 66 is disposed to engage a plurality ofcontact fingers 67 and 70, inclusive.

Assuming now that the master controller is thrown to its second positionb to engage contact fingers 67 to 70, inclusive, then current flows fromthe source 63 through conductor 71, contact fingers 70 and 69, bridgedby the contact segment 66, conductor 72, actuating coil 610 of theswitch 61, and thence back to the source 63, whereby switch 61 isclosed.

Another circuit established by the operation of the master controllerextends from contact finger through conductor 73, contact fingers and76, bridged by the contact segment 77 of the sequence drum 55, conductor78, actuating coil 620 of the switch .62, and conductor 79 to the sourceof supply. Accordingly, switch 62 is also closed, and the motors 56 areconnected across a section of the secondary winding of the transformer58.

The motor circuit extends from the secondary 57 of the transformerthrough switch 62 a portion of the preventive coil 112, conductor 113,the actuating coil 19 of the relay .36, conductor 114, the motors 56,switch '61 and conductor 115 to the negative side of the transformerwinding.

An interlock 107, that is disposed to engage contact fingers 108 and109, is carried by the switch 61. Therefore, when the switch 61'isclosed, the interlock 107 is moved into engagement with the contactfingers 1'08 and 109, thereby closing the actuating circuit of theswitch 60. This cir- .cuit may be traced from contact finger of themaster controller, through conductor 73, contact fingers 75 and 110,bridged by the contact segment 77 of sequence drum 55, con- .ductor 111,coil 600, conductor 112, cont-act fingers 109 and 108, bridged by theinterlock 107, and conductor 79 to the source 63, whereby the switch 60is closed.

Further, when the master controller is set in its first position a,current flows from the source 63 through conductor 71, contact fingers70 and 68, bridged by the contact segment 66, conductors 73 and 80,contact fingers 81 and 82, bridged by the contact segment 83 of thesequence drum 55, conductor 84, coil 44 of my control device, andconductors 85 and 79 to the negative side of the source of supply. Theenergization of the coil 44 effects the operation of the armature 36 andlifts the weight 34, thereby releasing the contact carrier 15.

It will also be understood that, as soon as the motors are connectedacross the secondary winding 57 of the transformer 58, a heavy currentwill flow in the coil 19. The energization of the coil 19 that is-causedby the initial current flowing in the motors is sufiicien't to raise thecontact carrier 15, which has been relieved of the weight 34.

Two circuits are also established, for energizing the actuating coilsthat effect the operation of the air-engine. The first circuit extendsfrom the source of power 63 through conductor 71, contact fingers 70 and68, bridged by the contact segment 66, conductor 73 and 86, theactuating coil 87, and conductor 88 to the source 63. The second circuitfor the air-engine extends from conductor 73 through conductor 80,contact fingers 81 and 89, bridged by the contact segment 83, ofsequence drum I55 conductor 90, actuating coil 91 and conductor 88 :tothe source. Since both the actuating coils 87 and 91 of the air-engineare energized, it functions to move the sequence drum .55 forward.

As soon as the sequence drum 55 reaches position a, the contact segment83 disengages the contact fingers 81 and 82, thereby interrupting theenergizing circuit of actuating coil 91. Until the current flowing inthe motor circuit has been reduced to a suflicient amount by thebuilding up of a counterelectromotive force, to permit the plunger 15 todrop, the coil 91 cannot be energized, the operation of the air-engineis stopped and the sequence drum 55 is thus caused to pause in positiona.

WVhen the contact finger 82 is disengaged from the contact segment 83,the coil 44 of my control device is deenergized, and the weight 34 maybe transferred to the plunger 15. During the transfer of the weight fromthe armature 36 to the plunger 15, the coil 4-1 is energized by beingconnected across a section of the secondary winding 57 of thetransformer 58. The circuit established extends from the secondarywinding 57 through conductor 92, coil 41, conductor 93, contact fingers94 and 95, bridged by .the contact segment 96, of sequence drum 55 andconductor 97 to the transformer. Therefore, a magnetic field throughwhich the arm 43 vmust pass is developed, and the movement of thearmature 36 is thereby retarded.

At approximately the same time that the energizing circuit for the coil44 is interrupted and before the weight 34'can be conductor 73, contactfingers 75 and 98,

bridged by the contact segment 77, and actuating coil 590 to negative79. In this manner, an increased voltage is applied to the motors and anincreased current flows in the coil 19. The energization of the coil 19is sufiicient to raise the plunger 15, with the weight 34 seatedthereon.

As will be readily understood, the coil 91 cannot be energized at thistime and, therefore, the sequence drum remains in position a. Uponbuilding .up-of an electromotive force in the motors 56, the currentflowing in the coil 19 is reduced and the plunger 15, under theinfluence of the Weight 34, tends to return the contact plate 26 intoengagement with the contact fingers 30. Upon lowering the plunger, a newcircuit is established which extends from'the source 63, throughconductor 71, contact fingers and 67, bridged by the contact segment 66,conductor 99, contact fingers 100 and 101, bridged by the contactsegment 102 of sequence drum 55, conductor 103, contact members '54'and51, conductor 104:, contact members 30, bridged by thecontact plate 26,conductor 105, contact fingers 106 and 89, bridged by the contactsegment 83 of sequence drum 55, conductor 90, actuating coil 91 of theair-engine and conductor 88 to the source. At this time, therefore, bothactuating coils 91 and 87 of the air-engine are energized, and thesequence drum is again moved forward to its position b.

As will be understood from the above description, my control devicefunctions to prevent the overrunning of the sequence drum and alsocauses the closure of the desired circuits to set the sequence drum inoperation to cause a further acceleration of the motors after the properelectromotive force has been built up to prevent the flow of anexcessive current.

Since various changes may be made in the above-described constructionand arrangement of parts, and different embodiments of i the inventionmay be made without departing from the scope of the invention as setforth in the appended'claims, it is intended that all matter containedin the above description and shown in the accompanying drawings shall beinterpreted as illustrative and not in a limiting sense.

I claim as my invention:

1. In control apparatus, in combination, a

movable contact carrier, means for restricting the operatiolr ofthecontact carrier, means for releasing the contact carrier from saidmeans'provided to restrict its operation, means for actuating thecontact carrier when subject to and when released from the restrictingmeans, and means for retarding the operation of said releasing means.

2. In control apparatus, in combination, a movable contact carrier,means for actuating the contact carrier, means removably mounted on thecontact carrier for restrlcting its operation, and means for releasingthe contact carrier from the means provided to restrict its operation.

3. In control apparatus, in combination, a movable contact carrier,means for actuating the contact carrier, a weight disposed to seat onthe contact carrier to restrict its operation, and means for lifting theweight to release the contact carrier.

4. In control apparatus, incombination, a movable contact carrier, meansfor actuating the contact carrier, a weight disposed to seat on thecontact carrier to restrict its operation, means for lifting the weightto release the contact carrier, 9 and electromagnetic means forretarding the operation of said lifting means.

5. In a limit relay, in combination, a verti-' cally disposed movablecontact carrier, electromagnetic means for actuating the contactcarrier, a weight disposed to seat on the contact carrier and adapted torestrictits operation, and electromagnetic means for removin the weightfrom the contact carrier.

6. In a limit relay, in combination, a vertically disposed movablecontact carrier, electromagnetic means for actuating the contactcarrier, a weight disposed to seat on the contact carrier disposed torestrict its operation, electromagnetic means for removing the weightfrom the contact carrier, and means for restricting the action of theweight-removing means.

7. In control apparatus, in combination, a vertically disposed movablecontact carrier, electromagnetic means for actuating the .contactcarrier, a weight slidably mounted on the contact carrier, a pivotallymounted armature disposed for operation to lift the weight, thereby torelieve the contactcarrier, and electromagnetic means for actuating saidarmature.

8. In control apparatus, in combination, a vertically disposed movablecontact carrier, electromagnetic means for actuating the contactcarrier, a weight slidably mounted on the contact carrier, a pivotallymounted armature disposed for operation to lift the weight, thereby torelease the contact carrier, electromagnetic means for actuating saidarmature, and electromagnetic means adapted to be periodically energizedfor retarding the operation of said armature.

9. In control apparatus, in combination, a vertically disposed movablecontact carrier, means for actuating the contact carrier, a Weightslidably mounted on the carrier, a pivotally mounted armature disposedfor operation to lift the Weight to permit the contact carrier to moveindependently thereof, electromagnetic means for actuating the armature,and an arm carried by said armature and means for developing a magneticfield to retard the movement of said arm, thereby to retard theoperation of the armature.

10. In control apparatus, in combination, a movable contact carrier,contact members provided on the contact carrier, a Weight disposed toseat on the contact carrier to restrict its operation, means foractuating the contact carrier When relieved of said Weight and whencarrying the Weight, and means for lifting the Weight from said contactcarrier to facilitate its operation.

In testimony whereof, I have hereunto subscribed my name this 2nd day ofOctober,

WALTER H. SMITH.

